8. The mass spectra below is for the hypochlorite ion, CIO. Oxygen has only one stable isotope, which has a mass of 16 amu. Relative abundance 40 45 50 55 a. How many neutrons does the most common isotope of chlorine have? Using the spectra, calculate the average mass of the hypochlorite ion. b. C. Does the negative charge on the ion affect the spectra? Justify your answer. d. The negative charge in the ion is located around the oxygen atom. Speculate as to why.

Average atomic masses listed by JUPAC are based on a study of experimental results. Bromine has two isotopes 79Br and 81Br, whose masses (78.9 183 and 80.9 163 amu) and abundances (50.69% and 49.3 1%) were determined in earlier experiments. Calculate the average atomic mass of bromine based on these experiments.

See the definition for isobars in Question 15. Consider Cr-54, Fe-54, Fess, and Ni-S8. (a) Which of these are isobars? Which are isotopes? (b) What do Fe-S4 and Fe-58 have in common? (c) Which atoms have the same number of neutrons?

The average atomic masses of some elements may vary, depending upon the sources of their ores. Naturally occurring boron consists of two isotopes with accurately known masses ( 10B, 10.0129 amu and 11B, 11.0931 amu). The actual atomic mass of boron can vary from 10.807 to 10.8 19, depending on whether the mineral source is from Turkey or the United States. Calculate the percent abundances leading to the two values of the average atomic masses of boron from these two countries.

In what way are isotopes of a given element always different? In what way(s) are they always the same?

How would you expect the chemical properties of isotopes of the same element to compare to each other? Explain your answer.

Scientists J. J. Thomson and William Thomson (Lord Kelvin) made numerous contributions to our understanding of the atom’s structure. Which subatomic particle did J. J. Thomson discover, and what did this lead him to postulate about the nature of the atom? William Thomson postulated what became known as the “plum pudding” model of the atom’s structure. What did this model suggest?

Your friend tells you about an article that he read in a tabloid that reported the discovery of a new form of carbon containing eight protons in the nucleus of its atoms. He claims that scientists are eager to explore the properties of this new form of carbon. What is wrong with the tabloid's claim? a. Nothing. The claim is believable. b. The claim must be false because an atom with eight protons would be oxygen, which is already known. c. The claim must be false because all forms of carbon are already known.

Radon is a radioactive gas that can cause lung cancer. It has been detected in the basement of some homes. In an atom of Rn-220, (a) how many protons are there? (b) how many neutrons are there?

One of the best indications of a useful theory is that it raises more questions for further experimentation than it originally answered. Does this apply to Daltons atomic theory? Give examples.